my guess is False i think that is the correct answer, because their are mammals that live in the tundra.
Digestive enzymes<span> speed up reactions that break down large molecules of carbohydrates, proteins, and fats into smaller molecules the body can use. Without digestive </span>enzymes<span>, animals would not be able to break down food molecules quickly enough to provide the energy and nutrients they </span>need<span> to </span><span>survive</span>
Type of chocolate bar, size of it, surface it is placed on, etc
Controlled variables are anything that stay the same for both trials
